Cooling and sealing means for disk atomizer shafts



Feb. 12, 1952 C. ANDERMATT 2,584,973

COOLING ANO SEALING MEANS FOR DISK ATONIZER sHAFTs Filed July 29, 1947INVENTOR CARL ANDERMATT BY MyW ATTORNEYS Patented Feb. l2, 1952 jYcooLING AND SEALING MEANS FOR *DISKk `Luwa, S. A., Zurich, Switzerland,a corporation of ,Switzerland Appiieatin -July 29, 1947, serial No.764,797 v- In Switzerland April'10, 1947 laims.

`1 .f The atomizing devices whichat the. present time are coming moreand more into .use in `which a liquid medium is centrifugally projectedby a rapidly rotating atomizing discagainst a current of hot air, theliquid dried in this .manner emerging from the process in the lform .ofa powder, impose very heavy demands on thebear-v ings of the atomizerdisc-shaft. :In the rst place, an obvious pre-requisite is that thebearings as such should be perfect, andin addition to this, in view ofthe high speed of rotation of the shaft, the bearing must be kept free.of all contamination. Furthermore', in View of the circumstance that intheV great majority of cases the materials to be -atomized aresubstances serving for human nourishment,:orsubstances sensitive to oil,the most painstaking care must be taken to ensure that no lubricantenters the atomizing or pulverizing chambers, since it is obvious thateven extremely small quantities of impurities would render unusable thepowder produced. Finally the fact must also be borne in mind that thecurrents of air Whose task it is todry the atomized liquid medium mustof necessity be at a high temperature, and this caneasily lead to theburning of the medium being dried, and to deposits being formed on thebearings..

These brief remarks are intended to show the enormous diiiiculties whicharise in connection with the provision of the atomizer shaft withbearings. 1.

It is true that, for the most varied purposes, the use of seals onrotating shafts is known, such seals being used for instance to-preventthe pressures existing in turbines from,..being dissipated to theexterior, or for sealing oi, eachfrom the other, chamberscontaining'liquids under pressure. However, none of the purposeshitherto known for the use of such washers or seals presents such anextensive range of requirements which the bearings must meet as does,the disposition of atomizer disc shafts in pulverization dehydratingplants. l

The object of the present invention is a device on or about the bearingsof high-speed atomizer shafts which device meets, as practical testsVhave shown, all lthe requirements mentioned in the preamble hereto,which are imposed on the bearings of high-speed atomizer shafts; 'n

The device in accordance with the present invention is characterized bythe fact that the shaft being sealed off against the shafts .and 'closedeach against the other, the bearing chamber being connected to oilSupply and discharge pipesor tubes, the following chamberbeingconnected` to a tension relievingpipe and the next chamber beingconnected to a gas. supply tube, thelast mentioned chamber .contactingthev shaftyby means of a wall possessing openings. permitting sent twotypical embodiments of the invention,

in which drawing:

Fig. 1 is a section through thebearing ofthe pulverizer disc in a rstembodiment; v

Figure 1A is a transverse sectional Vview .taken along the'line lA--lAof Figure 1;

\ Fig. 2 is a section through the bearing of-.the

pulverizer disc `in an alternative and Figure 2A is a transversesectional view taken along the line 2A-2A of Figure 2..` f

To shaft I is secured the atomizer disc 2. Shaft l -is driven byanyzselected source of power, for. instance an electric motor 3. Theshaftl is ,jour-v nalled in the housing 5 by means of thelball-bearingassembly 4. The housing 5is insertedf into theY container, not shown,which forms the atomizing chamber, the wall Y6 providing the. means ofseparation between'the chamber'i'i, which.,may`

for instance be open to the ambient air,and the chamber 8, whichcommunicates with thepulverizin-g or atomizing chamber. On the dividingWall 6 or a cylindrical tube 9 contiguous thereto, is

fitted an ordinary sealing collar I. :The sealingv collar I0 forms theupperflimit'of the :chamber II, in which is located the ball-bearingassembly 4. Through the pipey .I the .o il isffed into theV chamber IIand atomized by a centrifugal baillef ring I3 to form an oil vapourwhich lubricates thev ball-bearing assembly 4. Immediately below theball-bearing assembly 4, and likewise projecting into the chamber II, afurther centrifugal' baffle ring I4 is provided which projects theoilvapourr entering via the ball-bearing assembly towards! the oildischarge pipe I5, which' likewise' opens into the chamber' Il.

embodiment;

The chamber I-I is"closed againstthe shaft I vby means 4of a seal,forexample a labyrinth seal I6, this largely preventing the passage ofoil into the immediately succeeding pressure chamber The succeedingchamber similarly rests on the shaft by means of a labyrinth seal I8 andis provided, immediately below the labyrinth seal |'6 of the chamber |I,with a centrifugal baillev ring Hi. YThis baule ring serves theepurposeofiprojectingtowards the pressure relieving tube 2D any oilvapour which may nevertheless succeed in passing through the laby.- f

A ses supply ductVv chamber 33 from chamber 31 through the labyrinthseal 3| is evacuated through pipe 34. Portions of the sealing gassupplied will pass through the labyrinth seal 32 into the bearingchamber 38 and there serve to cool the ball-bearing assembly 28.

Via the. pipe 3% is fed the oilffor lubricating the ball-bearingassembly 29, and the centrifugal barde ring 4|] forms of it an oilvapour which supplied, preferably under pressure, the tempera.-v y

into; the. chamber 2|... Thewall; 2.4 by. means of which. the. chamber2|I restsagainstthe shaft possesses. small openings,. as for exampleslots. 25, which allow.l the. passage of the. gas. supplied through thevpipe 22.. The, gas is. evacuated in the. direction indicated bythearrows. Thisprovides a seal against the ingressof dust fromv thepulverizing chamber; and atthe. same. timecools the. pulverizing oratomizingv disc.. In the wall 23. borings 26 can, for example, beprovided, through. which borings. they gas; supplied through. the pipe22 can passA to. cooli. the. pulverizer disc. directly.4 In this.embodiment considerable quantities. of gas must be suppliedthroughthezpipen, in order to. ensure the maintenance.ofthe-.current ofsealinggas. throughthe. slots 25. Annular chamberV 8 is contiguous tothe annular chamber 26a,..

which latter` servesafor the. supply of thehot air used for drying ordehydrating purposes.

The gasnthechamber 2|; and serving. forcooling and sealing. purposes.can, however, alsotbe completely.- ory partially used., forthecoolingofthe.

motor 3 and; of. theL outer bearing.- Wallsof the.

bearing; chamber Forthatpurpose apassage 27|. im thewall .6, anopening.21a. rOmchamber: 8

to. chamber- 2|., and an outlet 2lb. for. chamber must-.be.pro,vided.VThe liquid is broughtto the disc 2, by. any. suitable. means not. shownyinthe drawings, for example, through. a. passageformed.

in the shaft.

In the. embodimentshown in Figure 2 a hydraulicY engine 28, forinstance, is; used instead. ofthe. electric motor for the drive of. theshaft A hydraulic enginel has the advantagev of regu-L lability of the.speed of revolution. withinwide limits. In thev embodiment. shown. inFig-ure` 2i twol ball-bearing assemblies 29 and 301 are pro-- penetratesinto. the. bearing 29. Chamber 38 Yalsofcontains the second bearing 30,it being pos- 'sible to provide, immediately above the bearing 30,.asecond oil supply pipe 4| and a centrifugal baille ring 42. The shaft isshown fractured in Fig. Z-soas to abbreviate the representation of thebearingy arrangement. The bottom of the bearingl chamber 38 is connectedto an oil discharge pipe 43 similarly to the embodiment in accordancewith Fig. 1.V The pressure chamber 44 which succeeds chamber 38 liesagain on a tension,4 relieving. pipe.l 45,. and the next. coolingchamber, 4.6.., isr again fed with.- gas. The, func.- tions of these`chambers. are the; same as in the embodimentin accordance with.- Fig. l.However, in the embodiment in accordance with Fig, 2 the supply of the;sealing. gas; is effected through the. ductformed. by. annularl chamber4l and borings 48 to the; chamber 46.. Ina second annular chamber. 49portions of the gas, fed; in are discharged. Whilst the annular chamber4;'| is directly contiguousy tov the. walls,- of the bearings, so. thatthe gasr fed through this; annular chamber cools, thebearing,y annularchamber 49 is contiguous to. the annular. chamber 5|),` which serves forthe.

supply of the hot air used for drying or dehydrati-ng. purposes;Thisarrangement prevents anexcessive transfer of.' heat from annularchamber; 50.v to, the bearingv chamber. The. pipe. 5 l: serves to,l feedin the: liquid'` medium. requiring. to be. atom.- izedV or pulverizedi.

The. atomzer or pulverizerl disc 2; isv provided in the. embodiment. inaccordance with FigureZrwith a cavityI 52, into, which the. liquidmedi-y um is fed via the; liquid feed' distributor chamber 53; andtheoutflow.v openingsv 54. disposed therein, Through the, slots. 55;provided in that wall of chamber 4.6.which is contiguous. to the shafta. portion of. thegassupplied is, in a similar mannerA tothat obtainingin. the case of the embodiment in. accordance, with Figure l, also fedto, the cavity 52 in the pulverizer disc 2, which latter it cools. The;liquid supplied then emerges through. the. openings55 in the pulverizer.disc 2r. is` atomized and comes. within range of the hotain suppliedthrough theannular chamber rand;

serving. forl drying or dehydrating purposes.

The two embodiments. illustrated should prove conclusively. that thedevice in accordance with the` invention ensures on the one handAcomplete sealing. oifof' the bearingl both in respectV of thepassageofflubricant*intothe pulverizing chamber from-the. bearingchamber; and that on. the. other, hand as a result of the suitableguidance; of the. current of:` sealing and cooling air those partsinregard'. to which. there exists. the danger ofthe. burning-on and rmdeposition of theA material; being pulverizedl are; adequately cooled.

I claim:

1. A cooling andisealing devicefor a discatom.- izer shaft carrying adisc enclosed in an atomizing chamber, saidi device comprising aball-bearing assembly. carryingv said shaft; means constituting casingwalls; formingv a bearing chamberv enclosing said: ball-bearingassembly, a pressurechamber adjacent-to saidbearing-chamber andA a:

cooling chamber adjacent to said atomizing chamber, some of the Walls ofsaid chambers enclosing said shaft; an oil supply pipe opening into saidbearing chamber; an oil discharge pipe communicating with said bearingchamber; a pressure-relieving pipe communicating with said pressurechamber; and a gas supply duct opening into said cooling chamber; saidcooling chamber having a wall located adjacent to said disc and havingopenings formed therein, whereby gas supplied to said cooling chamberthrough said gas supply duct cools the last-mentioned wall and providesa seal against the passage of oil vapor from said pressure chamber andagainst the passage of the dust from said atomizin'g chamber.

2. A device in accordance with claim 1, wherein said openings of thecooling chamber communicate with the atomizing chamber.

3. A device in accordance with claim 1, having means forming a liquidfeed distributor chamber located between said disc and said coolingchamber and adjacent to the openings of said cooling chamber, wherebygas emerging from said openings cools the Walls of said liquid feeddistributing chamber.

4. A device in accordance with claim 1, wherein said means include anannular chamber communicating with said cooling chamber to receive atleast'jsome of the gas supplied to said cooling chamber; and anotherannular chamber contiguous to the first-mentioned annular chamber andtransmitting hot air toward the disc.

5. A device in accordance with claim 1, having a motor driving saidshaft and wherein said means include means communicating with said gassupply duct for cooling a wall of said bearing chamber and said motor bya portion of the gas iiowing from said gas supply duct.

CARL ANDERMATT.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,677,119 Kinyon July 10, 19282,125,446 Hurtt Aug. 2, 1938 2,188,506 Hall Jan. 30, 1940 2,253,350 Rosset al Aug. 19, 1941 2,287,795 Hall June 30, 1942 2,299,119 Yeomans Oct.20, 1942 2,439,127 Dailey, Jr. et al Apr. 6, 1948

